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1.
bioRxiv ; 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38854015

RESUMO

The human aorta undergoes complex morphologic changes that indicate the evolution of disease. Finite element analysis enables the prediction of aortic pathologic states, but the absence of a biomechanical understanding hinders the applicability of this computational tool. We incorporate geometric information from computed tomography angiography (CTA) imaging scans into finite element analysis (FEA) to predict a trajectory of future geometries for four aortic disease patients. Through defining a geometric correspondence between two patient scans separated in time, a patient-specific FEA model can recreate the deformation of the aorta between the two time points, showing pathologic growth drives morphologic heterogeneity. A shape-size geometric feature space plotting the variance of the shape index versus the inverse square root of aortic surface area (δ𝒮 vs. ) quantitatively demonstrates the simulated breakdown in aortic shape. An increase in δ𝒮 closely parallels the true geometric progression of aortic disease patients.

2.
PLoS Comput Biol ; 20(2): e1011815, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38306397

RESUMO

Clinical imaging modalities are a mainstay of modern disease management, but the full utilization of imaging-based data remains elusive. Aortic disease is defined by anatomic scalars quantifying aortic size, even though aortic disease progression initiates complex shape changes. We present an imaging-based geometric descriptor, inspired by fundamental ideas from topology and soft-matter physics that captures dynamic shape evolution. The aorta is reduced to a two-dimensional mathematical surface in space whose geometry is fully characterized by the local principal curvatures. Disease causes deviation from the smooth bent cylindrical shape of normal aortas, leading to a family of highly heterogeneous surfaces of varying shapes and sizes. To deconvolute changes in shape from size, the shape is characterized using integrated Gaussian curvature or total curvature. The fluctuation in total curvature (δK) across aortic surfaces captures heterogeneous morphologic evolution by characterizing local shape changes. We discover that aortic morphology evolves with a power-law defined behavior with rapidly increasing δK forming the hallmark of aortic disease. Divergent δK is seen for highly diseased aortas indicative of impending topologic catastrophe or aortic rupture. We also show that aortic size (surface area or enclosed aortic volume) scales as a generalized cylinder for all shapes. Classification accuracy for predicting aortic disease state (normal, diseased with successful surgery, and diseased with failed surgical outcomes) is 92.8±1.7%. The analysis of δK can be applied on any three-dimensional geometric structure and thus may be extended to other clinical problems of characterizing disease through captured anatomic changes.


Assuntos
Aorta , Dissecção Aórtica , Humanos , Aorta/diagnóstico por imagem , Aorta/cirurgia , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/cirurgia
3.
Heliyon ; 9(9): e19473, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809556

RESUMO

In confined environments such as aircraft, an increase in mass impacts the overall system's performance, thus requiring sophisticated management. To verify whether the performance characteristics of fire extinguishing systems used in aircraft are satisfied, in this study was built a 1:1 scale test model. We examined the influence of the initial charge state and nozzles. Further, it measured the pressure inside the pipelines and vessels where multiple nozzles are installed to identify the flow and diffusivity characteristics of HFC-125 inside the pipelines and vessels. At a charging ratio of 54%, the initial pressure drop was smaller, and the lowest pressure before the bubble release point appeared 0.26 s later than when the charging ratio was 76%. The average pressure of each nozzle was 275.8 kPa higher under a charging ratio of 54% than 76% and increased further when the average concentration change was 54%, indicating that diffusivity increased. Although improvements occurred according to the charging ratio, the improvements according to the HFC-125 charging mass were more significant.

4.
Food Res Int ; 164: 112413, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36737994

RESUMO

Authentic honey products have a high commercial value and are often falsified via adulteration. Metabarcoding of environmental DNA (eDNA) from bacterial, floral, and entomological sources has recently been proposed as a useful tool for identifying and authenticating floral and geographical origins of bee honey. In this study, eDNA metabarcoding was applied to reveal the bacterial, plant, and honey bee DNA signatures of 48 commercial honey products from six different geographical origins. Bacterial DNA composition in commercial honey showed different relative abundance of Paenibacillus and Bacillus in geographically different samples, and high abundance of Methylobacterium in chestnut honey implying potential use of bacterial DNA composition for honey authentication. Using the chloroplast trnL (UAA) as a DNA marker, floral origins of commercial honey were investigated. Based on floral DNA signatures, 12 monofloral honey samples were identified among the 45 samples tested. Targeted amplicon sequencing of cytochrome oxidase I (COI) gene from entomological DNA identified three different Apis mellifera sequence variants, specific to geographic origin of honey, suggesting that COI can be implemented as a DNA marker to trace the origin of honey. Therefore, the current study demonstrated the potential of eDNA based metabarcoding as a robust tool for evaluating commercial bee honey by exploring their floral and geographical origins.


Assuntos
DNA Ambiental , Mel , Abelhas/genética , Animais , DNA Ambiental/genética , Marcadores Genéticos , DNA Bacteriano/genética , DNA
5.
JMIR Res Protoc ; 11(7): e36395, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35849426

RESUMO

BACKGROUND: Patient-reported outcome measures (PROMs) and patient-reported experience measures (PREMs) are self-reporting tools that can measure important information about patients, such as health priorities, experience, and perception of outcome. The use of traditional objective measures such as vital signs and lab values can be supplemented with these self-reported patient measures to provide a more complete picture of a patient's health status. Machine learning, the use of computer algorithms that improve automatically through experience, is a powerful tool in health care that often does not use subjective information shared by patients. However, machine learning has largely been based on objective measures and has been developed without patient or public input. Algorithms often do not have access to critical information from patients and may be missing priorities and measures that matter to patients. Combining objective measures with patient-reported measures can improve the ability of machine learning algorithms to assess patients' health status and improve the delivery of health care. OBJECTIVE: The objective of this scoping review is to identify gaps and benefits in the way machine learning is integrated with patient-reported outcomes for the development of improved public and patient partnerships in research and health care. METHODS: We reviewed the following 3 questions to learn from existing literature about the reported gaps and best methods for combining machine learning and patient-reported outcomes: (1) How are the public engaged as involved partners in the development of artificial intelligence in medicine? (2) What examples of good practice can we identify for the integration of PROMs into machine learning algorithms? (3) How has value-based health care influenced the development of artificial intelligence in health care? We searched Ovid MEDLINE(R), Embase, PsycINFO, Science Citation Index, Cochrane Library, and Database of Abstracts of Reviews of Effects in addition to PROSPERO and the ClinicalTrials website. The authors will use Covidence to screen titles and abstracts and to conduct the review. We will include systematic reviews and overviews published in any language and may explore additional study types. Quantitative, qualitative, and mixed methods studies are included in the reviews. RESULTS: The search is completed, and Covidence software will be used to work collaboratively. We will report the review using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and Critical Appraisal Skills Programme for systematic reviews. CONCLUSIONS: Findings from our review will help us identify examples of good practice for how to involve the public in the development of machine learning systems as well as interventions and outcomes that have used PROMs and PREMs. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/36395.

6.
J Clin Med ; 11(4)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35207327

RESUMO

In coronary artery bypass grafting (CABG) for patients on hemodialysis, there has been concern about "coronary steal". This study aims to evaluate the influence of using an in situ internal thoracic artery (ITA) ipsilateral to a preexisting arteriovenous fistula (AVF) in dialysis-dependent patients undergoing CABG. Between 2004 and 2018, dialysis-dependent patients with AVFs who underwent CABG were enrolled. According to the locational relationship of AVFs and in situ ITA grafts, the patients were divided into the ipsilateral group (n = 22) and the contralateral group (n = 21). Inverse probability weighting analysis was used to estimate and compare the late clinical outcomes. The late cardiac-related adverse events were not significantly different between the two groups: "major adverse cardiovascular and cerebrovascular events (MACCE)" (p = 0.090), "composite outcome of recurrent angina and coronary re-intervention" (p = 0.600). The in situ ITA graft of CABG on the ipsilateral side to AVF was not a significant risk factor for MACCE or the composite outcome of recurrent angina and coronary re-intervention. There was no statistically significant difference in the graft patency between the groups. Therefore, it might not be necessary to avoid using an in situ ITA on the ipsilateral side of an upper-arm AVF for optimal coronary artery bypass grafting in dialysis-dependent patients.

7.
ACS Appl Mater Interfaces ; 13(32): 37989-37996, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34346669

RESUMO

Liquid-liquid phase separation in an aqueous polymer solution is a unique physicochemical phenomenon, and the material present in the dense bottom layer is called a coacervate. A partial degree of water exclusion during coacervate formation often results in adhesive properties. The high viscosity makes coacervates incompatible with electrospinning processes. Coacervates can be electrospinnable only when the viscosity level of coacervates is adjusted. Electrospinning of coacervates results in a liquid-to-solid phase transition, addressing a long-term stability issue of coacervates. The preserved electrospun membranes can always be reconverted to a coacervate state by dissolution. Herein, we fabricate a spinnable coacervate solution using cosolvents. For neutral, hydrogen bond-dominated coacervates, such as those composed of poly(vinyl alcohol) (PVA) and phenolic tannic acid (TA), the use of a polar cosolvent system such as methanol-water results in an electrospinnable coacervate solution. The spun PVA-TA porous mats are a physicochemically stable solid, and the materials are converted back to an adhesive state upon wetting with body fluid. Considering the emerging studies related to coacervate adhesives, this study suggests that electrospinning a coacervate solution can be a strategy to dramatically increase the material stability and functionality.

8.
Appl Microbiol Biotechnol ; 105(7): 2775-2785, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33713143

RESUMO

Aromatic L-amino acid decarboxylases (AADCs) are ubiquitously found in higher organisms owing to their physiological role in the synthesis of neurotransmitters and alkaloids. However, bacterial AADC has not attracted much attention because of its rather limited availability and narrow substrate range. Here, we examined the biochemical properties of AADC from Bacillus atrophaeus (AADC-BA) and assessed the synthetic feasibility of the enzyme for the preparation of monoamine neurotransmitters. AADC-BA was expressed in Escherichia coli BL21(DE3) and the purified enzyme showed a specific activity of 2.6 ± 0.4 U/mg for 10 mM L-phenylalanine (L-Phe) at 37 °C. AADC-BA showed optimal pH and temperature ranges at 7-8 and 37-45 °C, respectively. The KM and kcat values for L-Phe were 7.2 mM and 7.4 s-1, respectively, at pH 7.0 and 37 °C. Comparison of the kinetic constants at different temperatures revealed that the temperature dependency of the enzyme was mainly determined by catalytic turnover rather than substrate binding. AADC-BA showed a broad substrate scope for various aromatic amino acids, including L-Phe, L-tryptophan (610% relative to L-Phe), L-tyrosine (12%), 3,4-dihydroxyphenyl-L-alanine (24%), 5-hydroxy-L-tryptophan (L-HTP, 71%), 4-chloro-L-phenylalanine (520%), and 4-nitro-L-phenylalanine (450%). Homology modeling and docking simulations were carried out and were consistent with the observed substrate specificity. To demonstrate the synthetic potential of AADC-BA, we carried out the production of serotonin by decarboxylation of L-HTP. The reaction yield of serotonin reached 98% after 1 h at the reaction conditions of 50 mM L-HTP and 4 U/mL AADC-BA. Moreover, we carried out preparative-scale decarboxylation of L-Phe (100 mM in 40-mL reaction mixture) and isolated the resulting 2-phenylethylamine (51% recovery yield). We expect that the broad substrate specificity of AADC-BA can be exploited to produce various aromatic biogenic amines. KEY POINTS: • AADC-BA showed broad substrate specificity for various aromatic amino acids. • The substrate specificity was elucidated by in silico structural modeling. • The synthetic potential of AADC-BA was demonstrated for the production of biogenic amines.


Assuntos
Descarboxilases de Aminoácido-L-Aromático , Bacillus , 5-Hidroxitriptofano , Descarboxilases de Aminoácido-L-Aromático/genética , Serotonina , Triptofano
9.
ACS Appl Mater Interfaces ; 12(18): 20933-20941, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32233363

RESUMO

Few studies aiming to develop a glue with an underwater reusable adhesive property have been reported because combining the two properties of reusable adhesion and underwater adhesion into a single glue formulation is a challenging issue. Herein, preparation of a simple mixture of poly(vinyl alcohol) (PVA) and a well-known phenolic compound, namely, tannic acid (TA), results in an underwater glue exhibiting reusable adhesion. We named the adhesive VATA (PVA + TA). Using VATA, two stainless steel objects (0.77 kg each) are able to be instantly attached. In addition to the high adhesive strength, surface-applied VATA in water retains its adhesive capability even after 24 h. In contrast, cyanoacrylate applied under the same water condition rapidly loses its adhesive power. Another advantage is that VATA's adhesion is reusable. Bonded objects can be forcibly detached, and then the detached ones can be reattached by the residual VATA. VATA maintains nearly 100% of its initial adhesive force, even after 10 repetitions of attach-detach cycles. VATA bonds various materials ranging from metals and polymers to ceramics. Particularly, we first attempt to test the toxicity of the underwater adhesives using an invertebrate nematode, Caenorhabditis elegans and gold fish (vertebrate) due to potential release to the environment.


Assuntos
Adesivos/química , Álcool de Polivinil/química , Taninos/química , Adesividade , Adesivos/toxicidade , Animais , Caenorhabditis elegans/efeitos dos fármacos , Carpa Dourada , Teste de Materiais , Álcool de Polivinil/toxicidade , Estresse Mecânico , Taninos/toxicidade , Resistência à Tração , Água/química
10.
Ann Vasc Surg ; 66: 554-565, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31706994

RESUMO

BACKGROUND: The association between oxidized low-density lipoprotein (OxLDL) and plaque instability in coronary and carotid artery disease is well established. However, the association between OxLDL and the histologic changes of plaque in peripheral artery disease has not been clearly elucidated. This study aims to investigate the association between plasma OxLDL and histologic plaque instability in patients with peripheral artery disease. METHODS: Prospectively obtained plaques from 48 patients who underwent endovascular atherectomy (n = 20), surgical endarterectomy (n = 9), or bypass surgery (n = 19) for treatment of atherosclerotic femoropopliteal artery disease were evaluated for histologic fibrosis, sclerosis, calcification, necrosis, cholesterol cleft, and foamy macrophages using hematoxylin and eosin, oil red O, and immunohistochemical staining. Unstable plaques were defined as plaques that were positive for foamy macrophages and with lipid content of more than 10% of the total plaque area. Plasma OxLDL levels were measured using an enzyme-linked immunosorbent assay (Mercodia AB, Uppsala, Sweden). RESULTS: Of the 48 patients, 26 (54%) had unstable plaques. The unstable plaque group was younger, had fewer angiographic total occlusions, less calcification, and more CD68-positive and LOX-1-positive cells than the stable plaque group. Plasma OxLDL levels were significantly higher in the unstable plaque group than in the stable plaque group (57.4 ± 13.9 vs. 47.2 ± 13.6 U/L, P = 0.014). Multivariate analysis revealed that plasma OxLDL level, smoking, angiographic nontotal occlusion, and statin nonuse were independent predictors of unstable plaque. CONCLUSIONS: Among patients with peripheral artery disease, the histologic instability of femoropopliteal plaque was independently associated with high plasma OxLDL, smoking, nontotal occlusion, and statin nonuse. Further large-scale studies are necessary to evaluate the role of noninvasive OxLDL measurement for predicting plaque instability and future adverse vascular event.


Assuntos
Lipoproteínas LDL/sangue , Doença Arterial Periférica/sangue , Doença Arterial Periférica/patologia , Placa Aterosclerótica , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/terapia , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , República da Coreia , Fatores de Risco , Ruptura Espontânea , Regulação para Cima
11.
J Microbiol Biotechnol ; 29(6): 887-896, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31216842

RESUMO

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS)-based pathogen identification relies on the ribosomal protein spectra provided in the proprietary database. Although these mass spectra can discern various pathogens at species level, the spectra-based method still has limitations in identifying closely-related microbial species. In this study, to overcome the limits of the current MALDI-TOF MS identification method using ribosomal protein spectra, we applied MALDI-TOF MS of low-mass profiling to the identification of two genetically related Bacillus species, the food-borne pathogen Bacillus cereus, and the insect pathogen Bacillus thuringiensis. The mass spectra of small molecules from 17 type strains of two bacilli were compared to the morphological, biochemical, and genetic identification methods of pathogens. The specific mass peaks in the low-mass range (m/z 500- 3,000) successfully identified various closely-related strains belonging to these two reference species. The intensity profiles of the MALDI-TOF mass spectra clearly revealed the differences between the two genetically-related species at strain level. We suggest that small molecules with low molecular weight, 714.2 and 906.5 m/z can be potential mass biomarkers used for reliable identification of B. cereus and B. thuringiensis.


Assuntos
Bacillus cereus/química , Bacillus cereus/classificação , Proteínas de Bactérias/química , Técnicas de Tipagem Bacteriana/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Bacillus/química , Bacillus/classificação , Bacillus/ultraestrutura , Bacillus cereus/ultraestrutura , Bacillus thuringiensis/química , Bacillus thuringiensis/classificação , Bacillus thuringiensis/ultraestrutura , Biomarcadores/química , DNA Bacteriano/genética , Doenças Transmitidas por Alimentos/microbiologia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Especificidade da Espécie
12.
Clinics (Sao Paulo) ; 72(8): 491-498, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28954009

RESUMO

OBJECTIVE:: The free radical theory of aging suggests that cellular oxidative damage caused by free radicals is a leading cause of aging. In the present study, we examined the effects of a well-known anti-oxidant amino acid derivative, selenocysteine, in response to environmental stress and aging using Caenorhabditis elegans as a model system. METHOD:: The response to oxidative stress induced by H2O2 or ultraviolet irradiation was compared between the untreated control and selenocysteine-treated groups. The effect of selenocysteine on lifespan and fertility was then determined. To examine the effect of selenocysteine on muscle aging, we monitored the change in motility with aging in both the untreated control and selenocysteine-treated groups. RESULTS:: Dietary supplementation with selenocysteine significantly increased resistance to oxidative stress. Survival after ultraviolet irradiation was also increased by supplementation with selenocysteine. Treatment with selenocysteine confers a longevity phenotype without an accompanying reduction in fertility, which is frequently observed in lifespan-extending interventions as a trade-off in C. elegans. In addition, the age-related decline in motility was significantly delayed by supplementation of selenocysteine. CONCLUSION:: These findings suggest that dietary supplementation of selenocysteine can modulate response to stressors and lead to lifespan extension, thus supporting the free radical theory of aging.


Assuntos
Envelhecimento/efeitos dos fármacos , Antioxidantes/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Selenocisteína/farmacologia , Fatores Etários , Animais , Caenorhabditis elegans/efeitos da radiação , Fertilidade/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Reprodutibilidade dos Testes , Reprodução/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Fatores de Tempo
13.
Clinics ; 72(8): 491-498, Aug. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-890723

RESUMO

OBJECTIVE: The free radical theory of aging suggests that cellular oxidative damage caused by free radicals is a leading cause of aging. In the present study, we examined the effects of a well-known anti-oxidant amino acid derivative, selenocysteine, in response to environmental stress and aging using Caenorhabditis elegans as a model system. METHOD: The response to oxidative stress induced by H2O2 or ultraviolet irradiation was compared between the untreated control and selenocysteine-treated groups. The effect of selenocysteine on lifespan and fertility was then determined. To examine the effect of selenocysteine on muscle aging, we monitored the change in motility with aging in both the untreated control and selenocysteine-treated groups. RESULTS: Dietary supplementation with selenocysteine significantly increased resistance to oxidative stress. Survival after ultraviolet irradiation was also increased by supplementation with selenocysteine. Treatment with selenocysteine confers a longevity phenotype without an accompanying reduction in fertility, which is frequently observed in lifespan-extending interventions as a trade-off in C. elegans. In addition, the age-related decline in motility was significantly delayed by supplementation of selenocysteine. CONCLUSION: These findings suggest that dietary supplementation of selenocysteine can modulate response to stressors and lead to lifespan extension, thus supporting the free radical theory of aging.


Assuntos
Animais , Envelhecimento/efeitos dos fármacos , Selenocisteína/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Antioxidantes/farmacologia , Reprodução/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Fatores de Tempo , Reprodutibilidade dos Testes , Fatores Etários , Caenorhabditis elegans/efeitos da radiação , Fertilidade/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Longevidade/efeitos dos fármacos
14.
Biosci. j. (Online) ; 33(2): 411-421, mar./apr. 2017. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-966195

RESUMO

Previous studies show that nutritional interventions with anti-oxidants have various healthpromoting effects in several model organisms. Here, we examine the effects of S-allyl cysteine on resistance to environmental stressors and age-related physiological changes using C. elegans as a model system. S-allyl cysteine is a modified amino acid found in aged garlic extracts and known to have strong anti-oxidant activity. The survival of worms under oxidative-stress conditions significantly increased with supplementation of S-allyl cysteine. In addition, pretreatment of S-allyl cysteine significantly increased resistance to both heat stress and ultraviolet irradiation. However, lifespan was not affected by S-allyl cysteine treatment. We also examined the effect of S-allyl cysteine on motility of C. elegans and found that S-allyl cysteine can retard the age-related decline of muscle tissue locomotive activity. S-allyl cysteine also significantly suppressed amyloid -induced paralysis in Alzheimer's disease model animals. Taken together, our study indicates that dietary supplementation of S-allyl cysteine can improve health span and suggests that S-allyl cysteine can be used to develop novel health-promoting pharmaceuticals.


Estudos anteriores mostram que intervenções nutricionais com antioxidantes têm vários efeitos promotores da saúde em vários organismos-modelo. Aqui, examinamos os efeitos da S-alil cisteína sobre a resistência a estressores ambientais e alterações fisiológicas relacionadas com a idade usando C. elegans como um sistema modelo. Salil cisteína é um aminoácido modificado encontrado em extratos de alho envelhecido e conhecido por ter forte atividade antioxidante. A sobrevivência de vermes sob condições de estresse oxidativo aumentou significativamente com a suplementação de S-alil cisteína. Além disso, o pré-tratamento com S-alil cisteína aumentou significativamente a resistência tanto ao estresse térmico como à irradiação ultravioleta. No entanto, o tempo de vida não foi afetado pelo tratamento com S-alil cisteína. Nós também examinamos o efeito da S-alil cisteína na motilidade de C. elegans e descobrimos que a S-alil cisteína pode retardar o declínio relacionado à idade da atividade locomotora do tecido muscular. A S-alil cisteína também suprimiu significativamente a paralisia induzida por amilóide em animais-modelo da doença de Alzheimer. Tomados em conjunto, o nosso estudo indica que a suplementação dietética de S-alil cisteína pode melhorar a duração da saúde e sugere que S-alil cisteína pode ser usada para desenvolver novos produtos farmacêuticos de promoção da saúde.


Assuntos
Caenorhabditis elegans , Cisteína , Alho , Antioxidantes
15.
Am J Cardiol ; 118(11): 1647-1654, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27742424

RESUMO

The value of late gadolinium-enhanced (LGE) magnetic resonance imaging (MRI) for the prediction of functional recovery after surgical revascularization has been previously established. However, the impact of LGE-MRI on the long-term prognosis after coronary artery bypass grafting (CABG) remains incompletely understood. Therefore, we aimed to evaluate the long-term prognostic value of LGE-MRI, based on the presence or absence of left ventricular (LV) dysfunction, in patients with coronary artery disease undergoing CABG. One hundred forty-six consecutive patients underwent cine- and LGE-MRI before CABG. Adverse cardiac events included cardiac death, nonfatal myocardial infarction, heart failure, and unstable angina. A 3-year landmark analysis of the primary end point was also performed for patients surviving beyond 3 years after CABG. During a median follow-up of 9.4 years, 44 patients (30%) experienced adverse cardiac events. Although a LV ejection fraction <50% was associated only with adverse cardiac events at 3 years after CABG, LGE was associated with a worse outcome both at and beyond 3 years after CABG. In the overall study population, LGE presence (adjusted hazard ratio [HR] 2.58; p = 0.027), score (adjusted HR 1.06; p <0.001), and extent (adjusted HR 1.08; p <0.001) were independent predictors of adverse cardiac events. Moreover, in both the LV ejection fraction <50% and ≥50% groups, the LGE extent was an independent predictor of adverse cardiac events. In conclusion, our qualitative and quantitative analyses of LGE-MRI provide long-term prognostic information after surgical revascularization. The LGE extent was a strong predictor of adverse cardiac events, independent of the LV function.


Assuntos
Ponte de Artéria Coronária , Doença da Artéria Coronariana/cirurgia , Gadolínio DTPA/administração & dosagem , Ventrículos do Coração/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética/métodos , Miocárdio/patologia , Disfunção Ventricular Esquerda/diagnóstico , Idoso , Meios de Contraste/administração & dosagem , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico , Diagnóstico Tardio , Feminino , Seguimentos , Ventrículos do Coração/fisiopatologia , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Período Pré-Operatório , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Tempo , Disfunção Ventricular Esquerda/complicações
16.
Food Chem Toxicol ; 85: 106-13, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26253354

RESUMO

Titanium dioxide (TiO2) nanoparticles are widely used in cosmetics, sunscreen, electronics, drug delivery systems, and diverse bio-application fields. In the workplace, the primary exposure route for TiO2 nanoparticles is inhalation through the respiratory system. Because TiO2 nanoparticles have different physiological properties, in terms of size and bioactivity, their toxic effects in the respiratory system must be determined. In this study, to determine the toxic effect of inhaled TiO2 nanoparticles in the lung and the underlying mechanism, we used a whole-body chamber inhalation system to expose A/J mice to TiO2 nanoparticles for 28 days. During the experiments, the inhaled TiO2 nanoparticles were characterized using a cascade impactor and transmission electron microscopy. After inhalation of the TiO2 nanoparticles, hyperplasia and inflammation were observed in a TiO2 dose-dependent manner. To determine the biological mechanism of the toxic response in the lung, we examined endoplasmic reticulum (ER) and mitochondria in lung. The ER and mitochondria were disrupted and dysfunctional in the TiO2-exposed lung leading to abnormal autophagy. In summary, we assessed the potential risk of TiO2 nanoparticles in the respiratory system, which contributed to our understanding of the mechanism underlining TiO2 nanoparticle toxicity in the lung.


Assuntos
Autofagia/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Pneumonia/induzido quimicamente , Mucosa Respiratória/efeitos dos fármacos , Titânio/toxicidade , Animais , Câmaras de Exposição Atmosférica , Biomarcadores/sangue , Relação Dose-Resposta a Droga , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/imunologia , Retículo Endoplasmático/patologia , Retículo Endoplasmático/ultraestrutura , Feminino , Hiperplasia , Exposição por Inalação , Pulmão/imunologia , Pulmão/patologia , Pulmão/ultraestrutura , Masculino , Nanopartículas Metálicas/administração & dosagem , Camundongos Endogâmicos A , Microscopia Eletrônica de Transmissão , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/imunologia , Mitocôndrias/patologia , Mitocôndrias/ultraestrutura , Tamanho da Partícula , Pneumonia/sangue , Pneumonia/imunologia , Pneumonia/patologia , Mucosa Respiratória/imunologia , Mucosa Respiratória/patologia , Mucosa Respiratória/ultraestrutura , Índice de Gravidade de Doença , Titânio/administração & dosagem , Testes de Toxicidade Subaguda
17.
PLoS One ; 10(6): e0131208, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26121477

RESUMO

Nanomaterials are used in diverse fields including food, cosmetic, and medical industries. Titanium dioxide nanoparticles (TiO2-NP) are widely used, but their effects on biological systems and mechanism of toxicity have not been elucidated fully. Here, we report the toxicological mechanism of TiO2-NP in cell organelles. Human bronchial epithelial cells (16HBE14o-) were exposed to 50 and 100 µg/mL TiO2-NP for 24 and 48 h. Our results showed that TiO2-NP induced endoplasmic reticulum (ER) stress in the cells and disrupted the mitochondria-associated endoplasmic reticulum membranes (MAMs) and calcium ion balance, thereby increasing autophagy. In contrast, an inhibitor of ER stress, tauroursodeoxycholic acid (TUDCA), mitigated the cellular toxic response, suggesting that TiO2-NP promoted toxicity via ER stress. This novel mechanism of TiO2-NP toxicity in human bronchial epithelial cells suggests that further exhaustive research on the harmful effects of these nanoparticles in relevant organisms is needed for their safe application.


Assuntos
Autofagia/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Membranas Intracelulares/metabolismo , Pulmão/patologia , Mitocôndrias/metabolismo , Nanopartículas/toxicidade , Titânio/toxicidade , Cálcio/metabolismo , Células Cultivadas , Retículo Endoplasmático/ultraestrutura , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Homeostase/efeitos dos fármacos , Humanos , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/ultraestrutura , Mitocôndrias/ultraestrutura , Nanopartículas/ultraestrutura , Espécies Reativas de Oxigênio/metabolismo , Ácido Tauroquenodesoxicólico/farmacologia
18.
Water Res ; 63: 285-95, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25016301

RESUMO

Lignin is the most abundant aromatic plant component in terrestrial ecosystems. This study was conducted to determine the contribution of lignin residues in natural water to the formation of disinfection byproducts (DBPs) in drinking water. We investigated the formation of different classes of DBPs from lignin model compounds, lignin polymers, and humic substances using two common disinfection techniques, chlorination and chloramination. The contributions of lignin to the overall formation of DBPs from these organic products were determined based on the observed abundances of individual lignin phenols and their DBP yields. Model lignin phenols generally produced higher trichloroacetic acid (TCAA) yields than chloroform and dichloroacetic acid (DCAA) during chlorination. Lignin phenols generally produced higher DBP yields but lower percentages of unknown total organic halogen compared to bulk humic substances and lignin polymers. The relative significance of lignin phenols as chlorination DBP precursors generally follows the order of TCAA > DCAA&chloroform. The relative significance of lignin phenols to DBP formation by chloramination follows the order: TCAA > DCAA&DCAN > chloroform. Overall, lignin phenols are more important as TCAA precursors than as chloroform and DCAA precursors.


Assuntos
Desinfetantes/metabolismo , Água Potável/análise , Lignina/metabolismo , Fenóis/metabolismo , Aminação , Cromatografia Líquida de Alta Pressão , Cobre/metabolismo , Desinfecção , Halogenação , Substâncias Húmicas/análise , Oxirredução , Polímeros/análise
19.
J Clin Biochem Nutr ; 53(2): 89-93, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24062605

RESUMO

Mithramycin A (Mith) is an aureolic acid-type polyketide produced by various soil bacteria of the genus Streptomyces. Mith inhibits myeloid cell leukemia-1 (Mcl-1) to induce apoptosis in prostate cancer, but the molecular mechanism underlying this process has not been fully elucidated. The aim of this study was therefore to investigate the detailed molecular mechanism related to Mith-induced apoptosis in prostate cancer cells. Mith decreased the phosphorylation of mammalian target of rapamycin (mTOR) in both cell lines overexpressing phospho-mTOR compared to RWPE-1 human normal prostate epithelial cells. Mith significantly induced truncated Bid (tBid) and siRNA-mediated knock-down of Mcl-1 increased tBid protein levels. Moreover, Mith also inhibited the phosphorylation of mTOR on serine 2448 and Mcl-1, and increased tBid protein in prostate tumors in athymic nude mice bearing DU145 cells as xenografts. Thus, Mith acts as an effective tumor growth inhibitor in prostate cancer cells through the mTOR/Mcl-1/tBid signaling pathway.

20.
Biosci Biotechnol Biochem ; 77(2): 320-3, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23391923

RESUMO

A gene encoding a novel organic solvent-tolerant alkaline lipase, lipS (GenBank ID JQ071496), was cloned from cold-adapted Pseudomonas mandelii. Recombinant LipS was expressed in Escherichia coli as a 32-kDa soluble protein and was purified by standard procedures. It maintained more than 80% of its activity under alkaline conditions, pH 8-10.5, with an apparent optimum temperature range of 40-50 °C. It maintained thermal stability from 4 to 50 °C. After 1 h of incubation at 60 °C, approximately 50% of its activity remained. It retained its activity in organic solvents, and activity increased in the presence of ethanol and of DMSO. Our data indicate that LipS is an alkaline lipase with relatively high thermal stability and notable tolerance of organic solvents.


Assuntos
Proteínas de Bactérias/química , Lipase/química , Pseudomonas/enzimologia , Álcalis , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Clonagem Molecular , Temperatura Baixa , Dimetil Sulfóxido/química , Estabilidade Enzimática , Escherichia coli/genética , Etanol/química , Concentração de Íons de Hidrogênio , Cinética , Lipase/genética , Dados de Sequência Molecular , Pseudomonas/química , Pseudomonas/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Alinhamento de Sequência , Solventes/química
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